The use of resistance potentiometers to set a wide variety of parameters, for example current, voltage or time, is known. In the case of resistance potentiometers, an analog change in resistance is tapped off and can be used directly in analog circuits, for example to change the gain. In the case of digital circuits, the analog change in resistance is read in with the aid of an analog/digital converter, for example, and is then processed. Although a resistance potentiometer in theory has an infinitely fine setting, a value can actually be set only with a limited level of accuracy on account of non-linearities, mechanical tolerances, reading inaccuracies etc. Therefore, complicated and expensive adjustment of the setting is generally necessary in the case of resistance potentiometers.
The prior art discloses a multiplicity of encoders. For example, the patent specifications U.S. Pat. Nos. 4,567,467 3,196,431, 3,187,318 and the patent application DE 198 03 661 A1 thus exhibit different encoders for signal coding. However, none of these encoders is used to set the functions in relays or the like.